well, there _is_ this:

https://en.wikipedia.org/wiki/Outer_Space_Treaty

"bars states party to the treaty from placing weapons of mass destruction in Earth orbit, installing them on the Moon or any other celestial body, or otherwise stationing them in outer space"

but 1. today's sentiment is: to hell with these treaties-schmeaties, and 2. what you mentioned is not yet a weapon of _mass_ destruction, so we're all good!